1. Field of the Invention
The present invention relates to a mobile communication system and method thereof. More particularly, the present invention relates to a home Base Transceiver Station (BTS) apparatus using a packet network as an interface network, instead of a dedicated interface network.
2. Description of the Related Art
Since their commercialization, mobile communication systems have been developed to be a promising substitute for wired telephony infrastructural communications. However, installation of dedicated interface networks between Mobile Stations (MSs) and Base Stations (BSs) involves high costs in the mobile communication systems.
FIG. 1 illustrates a network configuration of a conventional mobile communication system.
Referring to FIG. 1, the conventional mobile communication system includes a Mobile Switching Center (MSC) 130 for taking charge of calls with the mobile communication system and calls with a Public Switched Telephone Network (PSTN) 160, a Base Station Controller 140 (BSC) for taking charge of wireless calls with MSs 110 and 120 and connections to a Packet Support Node (PSN) 150 and the MSC 130, BTSs 165 and 167 for interfacing between the MSs 110 and 120 and the BSC 140 under the control of the BSC 140, and the PSN 150 for connecting the MSs 110 and 120 to an Internet 170. Network Elements 180 provide necessary information to other network elements.
The PSN 150 may include a Packet Data Serving Node (PDSN) and a Packet Control Function (PCF). The MS 110 can provide Internet connectivity as it is installed in a Personal Computer (PC) or a laptop computer in the form of a Personal Computer Memory Card International Association (PCMCIA) card or a Universal Serial Bus (USB).
The above network elements are interfaced based on the following interface standard.
FIG. 2 illustrates communication interfaces in the conventional mobile communication system.
Referring to FIG. 2, the interface standard is known as the InterOperability Standard (IOS) proposed for a Code Division Multiple Access (CDMA) mobile communication system.
After reference point signifies a point between BSs 250, 260, Aquinter reference point signifies a point between the BS 250 and PCF 240, and Aquarter reference point signifies a point between the PCF 240 and PDSN 235.
Each of BSs 250 and 260 has a BTS 257 or 267 and a BSC 255 and 265. The BSs 250 and 260 are connected by A3 and A7 interfaces. The A3 interface carries signals and traffic and the A7 interface is used for signaling.
The BSs 250 and 260 are connected to a PCF 240 by an A9 interface for signaling and an A6 interface for traffic transmission.
The PCF 240 is connected to a PDSN 235 by an A11 interface for signaling and an A10 interface for traffic transmission. The PDSN 235 is connected to the Internet and equipped with routing, billing, and Point-to-Point Protocol (PPP) connection functions.
The BSs 250 and 260 are connected to an MSC 230 by an Al interface for signaling and A2 and A5 interfaces for traffic transmission.
The MSC 230 is connected to an InterWorking Function (IWF) 232, for providing data service to MSs. The data service is available to the MSs through the PCF 240 and the IWF 232 in CDMA 2000 1× and its successors.
Physical standards, E1/T1, Optic, Satellite, Microwave, etc. can support the above-described dedicated interfaces.
Because dedicated interfaces are needed between the BSs 150 and 260 and the MSC 230, there may exist areas in which mobile communication services are not available due to the absence of such dedicated interfaces.
Accordingly, there exists a need for an improved apparatus for enabling signaling and data transmission between network elements without using a dedicated interface.